Complete anterior cruciate ligament tear and the risk for cartilage loss and progression of symptoms in men and women with knee osteoarthritis

OBJECTIVE: To determine whether a complete anterior cruciate ligament (ACL) tear, a frequent incidental finding on magnetic resonance imagings (MRIs) of individuals with established knee osteoarthritis (OA), increases the risk for further knee OA progression. METHODS: We examined 265 participants (43% women) with symptomatic knee OA in a 30-month, prospective, natural history study of knee OA. The more symptomatic knee was imaged using MRI at baseline, 15 and 30 months. Cartilage was scored at the medial and lateral tibiofemoral joint and at the patellofemoral joint using the Whole-Organ MRI Score (WORMS) semi-quantitative method. Complete ACL tear was determined on baseline MRI. At each visit, knee pain was assessed using a knee-specific visual analog scale and physical function was assessed using the Western Ontario and McMaster Universities (WOMAC) physical function subscale. RESULTS: There were 49 participants (19%) with complete ACL tear at baseline. Adjusting for age, body mass index, gender and baseline cartilage scores, complete ACL tear increased the risk for cartilage loss at the medial tibiofemoral compartment [odds ratio (OR): 1.8, 95% confidence interval (CI): 1.1, 3.2]. However, following adjustment for the presence of medial meniscal tears, no increased risk for cartilage loss was further seen (OR: 1.1, 95% CI: 0.6, 1.8). Knee pain and physical function were similar over follow-up between those with and without a complete ACL tear. CONCLUSIONS: Individuals with knee OA and incidental complete ACL tear have an increased risk for cartilage loss that appears to be mediated by concurrent meniscal pathology. The presence of a complete ACL tear did not influence the level of knee pain or physical function over short-term follow-up.     

Effect of fatty acids on bone marrow lesions and knee cartilage in healthy, middle-aged subjects without clinical knee osteoarthritis

OBJECTIVE: There is evidence that omega-3 polyunsaturated fatty acids alleviate the progression of osteoarthritis (OA). However, little work has been done to investigate the effect of fatty acids on bone marrow lesions and knee cartilage in healthy subjects. We examined this in a cohort of healthy middle-aged subjects without clinical knee OA. METHODS: Two hundred and ninety-three healthy adults without knee pain or injury were recruited from an existing community-based cohort. Intakes of fatty acids and food sources of these were estimated from a food frequency questionnaire at baseline. Tibial cartilage volume, tibial plateau bone area, tibiofemoral cartilage defects and bone marrow lesions were assessed approximately 10 years later using magnetic resonance imaging. RESULTS: In multivariate analyses, higher intakes of monounsaturated fatty acids (OR=2.14, 95% CI 1.04-4.39, P=0.04), total (OR=1.77, 95% CI 1.13-2.77, P=0.01) and n-6 polyunsaturated fatty acids (OR=1.69, 95% CI 1.10-2.61, P=0.02) were associated with an increased risk of bone marrow lesions. Intake of fatty acids was not significantly associated with cartilage volume or cartilage defects. CONCLUSION: These findings support the dietary recommendation towards a shift to foods rich in n-3 polyunsaturated fatty acids in order to maintain an optimal balance between dietary n-3 and n-6 polyunsaturated fatty acids, which is also important in the prevention of atherosclerosis. Although our findings will need to be confirmed in longitudinal studies, they suggest the potential of fatty acids to adversely effect the knee joint.     

Elevated tibiofemoral articular contact stress predicts risk for bone marrow lesions and cartilage damage at 30 months

OBJECTIVE: As cartilage loss and bone marrow lesions (BMLs) are associated with knee joint pain and structural worsening, this study assessed whether non-invasive estimates of articular contact stress may longitudinally predict risk for worsening of knee cartilage morphology and BMLs. DESIGN: This was a longitudinal cohort study of adults aged 50-79?years with risk factors for knee osteoarthritis. Baseline and follow-up measures included whole-organ magnetic resonance imaging score (WORMS) classification of knee cartilage morphology and BMLs. Tibiofemoral geometry was manually segmented on baseline magnetic resonance imaging (MRI), and three-dimensional (3D) tibiofemoral point clouds were registered into subject-specific loaded apposition using fixed-flexion knee radiographs. Discrete element analysis (DEA) was used to estimate mean and peak contact stresses for the medial and lateral compartments. The association of baseline contact stress with worsening cartilage and BMLs in the same subregion over 30?months was assessed using conditional logistic regression. RESULTS: Subjects (N?=?38, 60.5% female) had a mean?±?standard deviation (SD) age and body mass index (BMI) of 63.5?±?8.4?years and 30.5?±?3.7?kg/m(2) respectively. Elevated mean articular contact stress at baseline was associated with worsening cartilage morphology and worsening BMLs by 30?months, with odds ratio (OR) [95% confidence interval (CI)] of 4.0 (2.5, 6.4) and 6.6 (2.7, 16.5) respectively. Peak contact stress also was significantly associated with worsening cartilage morphology and BMLs {1.9 (1.5, 2.3) and 2.3 (1.5, 3.6)}(all P?相似文献   

Comparison of conventional standing knee radiographs and magnetic resonance imaging in assessing progression of tibiofemoral joint osteoarthritis

OBJECTIVE: Although the current recommendation is to measure radiographic joint space width (JSW) to assess structural change in osteoarthritis (OA), there is increasing interest in direct measurement of cartilage volume from magnetic resonance imaging (MRI). We performed a longitudinal study to compare change in both JSW and articular cartilage volume in subjects with symptomatic knee OA. METHODS: JSW was measured in 28 subjects with knee OA (57% females, mean age 62.8+/-9.8 years) who had standing radiographs in full extension, where both radiographs had satisfactory alignment. Each subject had femoral, tibial and combined femoral and tibial cartilage volumes determined from T1-weighted fat saturated sagittal knee MRI. All subjects had a repeat of the knee radiograph and MRI 1.96+/-0.4 years later. RESULTS: At baseline there was a moderate, but statistically significant, correlation between JSW and femoral and tibial cartilage volumes in the medial tibiofemoral joint, which was strengthened by adjusting for medial tibial bone size (R=0.58-0.66, P=0.001). Although we observed a reduction in JSW and femoral and tibial cartilage volumes over the study period, there was no significant association between reduction in JSW and cartilage volume (R<0.13). There was a trend towards a significant association between change in medial tibiofemoral cartilage volume and joint replacement at 4 years (OR=9.0, P=0.07) but not change in medial tibiofemoral JSW (OR=1.1, P=0.92). CONCLUSIONS: Although there was a modest correlation between cartilage volume and JSW in the medial tibiofemoral compartment, there was no correlation between longitudinal change in these measures. Change in cartilage volume appears to be a better predictor of joint replacement. Further work in larger samples over a longer period of time will be needed to confirm these findings.     

The associations between parity, other reproductive factors and cartilage in women aged 50-80 years

Objective

Sex hormones and reproductive factors may be important for osteoarthritis (OA). The aim of this study was to describe the associations of parity, use of hormone replacement therapy (HRT) and oral contraceptives (OCs) with cartilage volume, cartilage defects and radiographic OA in a population-based sample of older women.

Design

Cross-sectional study of 489 women aged 50–80 years. Parity, use of HRT and OC was assessed by questionnaire; knee cartilage volume and defects by magnetic resonance imaging and knee joint space narrowing (JSN) and osteophytes by X-ray.

Results

Parity was associated with a deficit in total knee cartilage volume [adjusted β = −0.69 ml, 95% confidence interval (CI) −1.34, −0.04]. Increasing parity was associated with decreasing cartilage volume in both the tibial compartment and total knee (both P trend <0.05). Parity was also associated with greater cartilage defects in the patella compartment [adjusted odds ratio (OR) = 2.87, 95% CI = 1.39, 5.93] but not other sites. There was a consistent but non-significant increase in knee JSN (OR = 2.78, 95% CI = 0.75, 10.31) and osteophytes (OR = 1.69, 95% CI = 0.59, 4.82) for parous women. Use of HRT and/or OC was not associated with cartilage volume, cartilage defects or radiographic change.

Conclusions

Parity (but not use of HRT or OC) is independently associated with lower cartilage volume primarily in the tibial compartment and higher cartilage defects in the patella compartment in this population-based sample of older women.     

Infrapatellar fat pad volume and Hoffa-synovitis after ACL reconstruction: Association with early osteoarthritis features and pain over 5 years

Infrapatellar fat pad (IPFP) morphology and Hoffa-synovitis may be relevant to the development and progression of post-traumatic osteoarthritis (OA). We aimed to compare IPFP volume and Hoffa-synovitis in participants with anterior cruciate ligament reconstruction (ACLR) and uninjured controls, and to determine their association with prevalent and worsening early knee OA features and pain in participants post-ACLR. We assessed IPFP volume and Hoffa-synovitis from magnetic resonance imaging (MRI) in 111 participants 1-year post-ACLR and 20 uninjured controls. Patellofemoral and tibiofemoral cartilage and bone marrow lesions (BMLs) were assessed from MRIs at 1 and 5 years post-ACLR, and worsening defined as any longitudinal increase in lesion size/severity. IPFP volume and Hoffa-synovitis prevalence were compared between groups with analysis of covariance and χ ² tests, respectively. Generalized linear models assessed the relation of IPFP volume and Hoffa-synovitis to prevalent and worsening features of OA and knee pain (Knee injury and Osteoarthritis Outcome Score—Pain Subscale, Anterior Knee Pain Scale). No significant between-group differences were observed in IPFP volume (ACLR 34.39 ± 7.29cm³, Control 34.27 ± 7.56cm³) and Hoffa-synovitis (ACLR 61%, Control 80%). Greater IPFP volume at 1-year post-ACLR was associated with greater odds of patellofemoral BMLs at 1-year (odds ratio [OR] [95% confidence intervals]: 1.104 [1.016, 1.200]) and worsening tibiofemoral cartilage lesions at 5-year post-ACLR (OR: 1.234 [1.026, 1.483]). Hoffa-synovitis at 1-year post-ACLR was associated with greater odds of worsening patellofemoral BMLs at 5-year post-ACLR (OR: 7.465 [1.291, 43.169]). In conclusion, IPFP volume and Hoffa-synovitis prevalence are similar between individuals 1-year post-ACLR and controls. Greater IPFP volume and Hoffa-synovitis appear to be associated with the presence and worsening of some early OA features in those post-ACLR, but not pain.     

Risk factors in familial osteoarthritis: the GARP sibling study

PURPOSE: To investigate the association between systemic and local risk factors and familial osteoarthritis (OA) at multiple sites. METHODS: Patients and their siblings had primary OA at multiple sites at middle age. OA diagnosis followed the American College of Rheumatology criteria. We recruited 345 controls (mean age 57 years (range 40-76), 64% women) by random sampling from the population by telephone and collected all data by questionnaires. Odds ratios (ORs) were adjusted for sex, age and body mass index (BMI) (kg/m(2)), 95% confidence intervals (CIs95) were computed using robust standard errors with the intra-family effect taken into account. RESULTS: Three hundred and eighty-two patients (mean age 60 years [range 43-79]), 82% women had OA in the spine (80%), hands (72%), knees (34%) and hips (24%). In women, an association of familial OA with a young age at natural menopause (<45 years), OR=2.6 (CI95 1.5-4.5) was found. Physically demanding jobs led to an increased risk of familial OA in men: OR=2.6 (CI95 1.3-5.3). Familial OA was more prevalent in individuals with a BMI>30, OR=2.0 (CI95 1.3-3.2) compared to a BMI of <25. Taller persons had a lower risk of familial OA, OR=0.33 (0.1-0.8) in the height category >180 cm relative to a height of <160 cm. A history of meniscectomy, increased the risk of familial OA at multiple sites with knee involvement, OR=6.2 (CI95 3.0-12.7). CONCLUSIONS: Systemic and local risk factors play a role in the etiology of familial OA at multiple sites.     

IGF-1基因5’端功能性SNP与中国汉族人群膝关节骨关节炎的相关性研究

背景：骨关节炎（osteoarthritis,OA）是最常见的关节炎,尤其在老年人群中发病率更高,它是包括遗传因素在内的多因素致病疾病。已有多项研究发现,许多基因与OA的易感性有密切关系。胰岛素样生长因子1（insulin likegrowth factor 1,IGF-1）可以促进软骨细胞合成软骨中的细胞外基质。IGF一1及其受体在软骨的发育及成年后重塑阶段均具有重要功能,并可能与OA的病因具有相关性。目的：IGF-1基因启动子区域-1245C／T位点（rs35767）单核苷酸多态性（single nucleotide polymorphisms,SNP）与膝关节OA的关系。方法：采用序列特异性引物PCR及探针法,检测中国汉族人群中具有临床症状且有影像学证据的524例原发性膝关节OA患者与540例健康对照者IGF-1基因启动子区域-1245C／T位点等位基因分布,分析-1245C／T位点等位基因与膝关节OA的相关性。结果：OA组与正常对照组比较,IGF-1基因启动子区域-1245C／T位点的基因型频率及等位基因频率分布无显著性差异（P=0．35、0．14）。按OA严重程度分组（中重度组患者均为K／L分级3、4级,轻度组为K／L分级2级）,中重度组与正常对照组比较,基因型分布无显著性差异（P=0．10）,等位基因频率分布有显著性差异（P=0．04）;但CC型与其它基因型（TT、TC）分布有显著性差异（P=0．03）。正常对照组中TT＋TC所占比例较中重度OA组多,OR=1．36,CI=[1．03,1．80]。逻辑回归分析示,上述差异为年龄、BMI及性别差异所致,与m35767的等位基因、基因型频率分布无显著相关性。结论：中国汉族人群的OA易感性与年龄、BMI、性别构成相关,与IGF-1基因启动子区域-1245C／T位点（rs35767）基因多态性可能无关。     

A meta-analysis of sex differences prevalence, incidence and severity of osteoarthritis

OBJECTIVE: To resolve uncertainty regarding sex differences in osteoarthritis (OA) by performing a meta-analysis of sex differences in OA prevalence, incidence and severity. METHODS: Standard search strategies for population-based studies of OA providing sex-specific data. Random effects meta-analysis to provide pooled male vs female risk and rate ratios for prevalent and incident OA, and standardized mean differences (SMD) for OA severity. Meta-regression was used to investigate sources of heterogeneity. RESULTS: Males had a significantly reduced risk for prevalent OA in the knee [Risk Ratio (RR) 0.63, 95% CI 0.53-0.75] and hand [RR 0.81, 95% CI 0.73-0.90] but not for other sites. Males aged <55 years had a greater risk of prevalent cervical spine OA [RR 1.29, 95% CI 1.18-1.41]. Males also had significantly reduced rates of incident OA in the knee [Incidence Rate Ratio (IRR) 0.55, 95% CI 0.32-0.94] and hip [IRR 0.64, 95% CI 0.48-0.86], with a trend for hand [IRR 0.65, 95% confidence interval (CI) 0.35-1.20]. Females, particularly those > or = 55 years, tended to have more severe OA in the knee but not other sites. Heterogeneity in the estimates of sex differences in prevalence was substantially explained by age and other study design factors including method of OA definition. CONCLUSIONS: The results demonstrate the presence of sex differences in OA prevalence and incidence, with females generally at a higher risk. Females also tend to have more severe knee OA, particularly after menopausal age. The site differences indicate the need for further studies to explore mechanisms underlying OA.     

Bone mineral density is cross sectionally associated with cartilage volume in healthy, asymptomatic adult females: Geelong Osteoporosis Study

Introduction

The association between osteoporosis and osteoarthritis (OA) is controversial. Although previous studies have shown total body, lower limb, spinal and knee BMD and knee cartilage volume to be positively associated, the relationship between other distant site-specific measures of BMD and other knee structures is unknown. The aim of this study was to determine the associations between BMD at eight skeletal sites, and knee structure in asymptomatic young to middle-aged females without any clinical signs of OA.

Methods

One hundred and sixty healthy, asymptomatic females (29–50 yr) underwent magnetic resonance imaging of the knee. BMD was measured at the spine, hip, total body and forearm by dual energy X-ray absorptiometry, and at the calcaneus by quantitative ultrasound. BMD was tested for an association with cartilage volume, defects, and bone marrow lesions (BMLs).

Results

Medial cartilage volume was positively associated with BMD at the spine, total body, femoral neck, and Ward's triangle (all p < 0.05), with non-significant associations in the same direction at the trochanter (p = 0.07). Findings in the lateral compartment were similar. The presence of medial cartilage knee defects were also associated with BMD at the spine; defects in the lateral compartment were associated with BMD at the forearm (both p = 0.05). BMD was not associated with the presence of BMLs. No associations were observed with calcaneus BMD.

Conclusions

Site-specific BMD is associated with cartilage volume at the knee in asymptomatic young to middle-aged adults, with the direction and effects trending in the same direction. The magnitude of changes correlates with clinically relevant changes. QUS defined calcaneus BMD, showed no associations with knee structure. Although systemic factors may underlie the association between knee cartilage volume and axial/lower limb BMD, these data suggest that common local, possibly biomechanical factors may also play a role.     

Knee cartilage defects: association with early radiographic osteoarthritis, decreased cartilage volume, increased joint surface area and type II collagen breakdown

OBJECTIVE: To generate hypotheses regarding the associations between knee cartilage defects and knee radiographic osteoarthritis (ROA), cartilage volume, bone size and type II collagen breakdown in adults. METHODS: A cross-sectional convenience sample of 372 male and female subjects (mean age 45 years, range 26-61) was studied. Knee cartilage defect score (0-4) and prevalence (a defect score of > or =2), cartilage volume, and bone surface area were determined using T1-weighted fat saturation MRI. Urinary levels of C-terminal crosslinking telopeptide of type II collagen (U-CTX-II) were measured by enzyme-linked immunosorbent assay. Height, weight and ROA were measured by standard protocols. RESULTS: In multivariate analysis, the severity and prevalence of knee cartilage defects were significantly and independently associated with tibiofemoral osteophytes (regression coefficient (beta): +0.86 to +1.31/unit, odds ratio (OR): 2.97-3.68/unit, all P<0.05 with the exception of OR in lateral tibiofemoral compartment) and tibial bone area (beta: +0.11 to +0.25/cm2; OR: 1.33-1.58/cm2, all P<0.01). Knee cartilage defects were inconsistently associated with joint space narrowing after adjustment for osteophytes but consistently with knee cartilage volume (beta: -0.27 to -0.70/ml; OR: 0.16-0.56/ml, all P<0.01 except for OR at lateral tibial cartilage site P=0.06). Lastly, knee cartilage defect severity was significantly associated with U-CTX-II (Partial r=+0.18, P<0.001 for total cartilage defect score). CONCLUSION: Osteophytes and increasing knee bone size may be causally related to knee cartilage defects. Furthermore, knee cartilage defects may result in increased cartilage breakdown leading to decreased cartilage volume and joint space narrowing suggesting an important role for knee cartilage defects in early knee OA.     

Static knee alignment is associated with the risk of unicompartmental knee cartilage defects

Although knee malalignment is a risk factor for the progression of unicompartmental knee osteoarthritis (OA), it is unclear how this relationship is mediated. Cartilage defects are known to predate cartilage loss and the onset of knee OA, and it may be that knee malalignment increases the risk of unicompartmental knee cartilage defects. Knee radiographs and MRI were performed on a total of 202 subjects, 36.6% of whom had radiographic knee OA, to determine the relationship between static knee alignment and knee cartilage defects. Analyses were performed for the entire cohort, as well as for healthy and OA subgroups. For every 1° increase in a valgus direction, there was an associated reduced risk of the presence of cartilage defects in the medial compartment of subjects with knee OA (p = 0.02), healthy subjects (p = 0.002), and the combined (p < 0.001) group. Moreover, for every 1° increase in a valgus direction, there was an associated increased risk of the presence of lateral cartilage defects in the OA group (p = 0.006), although the relationship between change toward genu valgum and lateral compartment cartilage defects did not persist for the healthy group (p = 0.16). This cross‐sectional study has demonstrated that knee alignment is associated with the risk for compartment specific knee cartilage defects in both healthy and arthritic people. Given that the natural history of cartilage volume reduction appears to be predated by the presence of cartilage defects, whether knee alignment affects the longitudinal progression from cartilage defects to cartilage loss requires further examination. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:225–230, 2008     

The association between joint stress from physical activity and self-reported osteoarthritis: an analysis of the Cooper Clinic data

OBJECTIVE: The purpose was to evaluate the association between estimated joint stress from physical activity (PA) and hip/knee osteoarthritis (OA). DESIGN: A nested case-control study was performed using data from the Aerobics Center Longitudinal Study. Participants without self-reported OA at baseline who attended the clinic between 1974 and 1993 and returned a follow-up questionnaire in 1990 or 1995 were eligible. Cases were those who reported a physician diagnosis of OA of the knee and/or hip at follow-up (N = 415). A random sample of persons in the remaining cohort were classified as controls (N = 1995). PA was measured at baseline by self-report and subjects were classified as 'moderate/high' or 'low' joint stress by PA type. Those reporting no PA were classified as sedentary with 'no' joint stress (the reference group). Men and women were analyzed separately. Stratified analysis and multiple logistic regression were used to assess the relationship between hip/knee OA and joint stress as predicted by PA. RESULTS: After adjustment for age, body mass index, years of follow-up, and history of hip/knee joint injury, among men, there was no association between hip/knee OA and low joint stress while moderate/high joint stress was associated with reduced risk of hip/knee OA (adjusted odds ratio (OR) = 0.62, 95% confidence interval (CI) = 0.43-0.89). Among women, both levels of joint stress were associated with reduced risk of hip/knee OA (OR = 0.58, 95% CI = 0.34-0.99 for low and OR=0.24, 95% CI = 0.11-0.52 for moderate/high). CONCLUSIONS: PA may reduce the risk of hip/knee OA, especially among women. Further research should assess the combined effects of frequency, intensity, duration and joint stress level of PA on incidence of hip/knee OA.     

Sagittal plane movement at the tibiofemoral joint influences patellofemoral joint structure in healthy adult women

OBJECTIVES: The influence exerted on cartilage and bone volumes by locomotor patterns is poorly understood, particularly at the patellofemoral joint. The aim of this study was to investigate the relationship between sagittal plane movement at the tibiofemoral joint and patella cartilage and bone volumes during the locomotion of healthy adult females. METHODS: Three-dimensional Vicon gait analyses and magnetic resonance imaging were performed on 20 healthy adult women. The relationships between the degree of tibiofemoral flexion and extension at varying stages of the gait cycle and the concomitant medial, lateral and total patella cartilage and total bone volumes were examined. RESULTS: For every degree the knee flexed during mid-stance, there was a 62.8 microL (95% confidence interval 3.7-122.0) increase in the medial patella facet cartilage volume after adjustment for age and the body mass index (BMI) (P = 0.04). A similar relationship that approached significance was observed for the lateral patella facet cartilage volume after adjustment for age and the BMI (P = 0.08). No association was observed between the sagittal plane tibiofemoral movements and the patella bone volume. CONCLUSIONS: The association between patella cartilage volume and tibiofemoral knee movement suggests that for every degree increase in knee flexion during mid-stance, there is an associated increase in patella cartilage volume. This may be the result of the geometry of the femoral condyle influencing patella tracking and or the retropatellar load exerted on the patella during walking. These results may have important implications for people who hyperextend their knee during gait and the pathogenesis of patellofemoral osteoarthritis.     

Prevalence, patterns, and risk factors of knee osteoarthritis in Thai monks

Background Patterns and risk factors of knee osteoarthritis in Asian countries where most people have habitual knee bending activities remain unclear. The objective of this study was to evaluate the prevalence, patterns, and risk factors of knee osteoarthritis in Thai monks. Methods The study was a cross-sectional survey of monks who lived in temples in southern Thailand. Investigations included history, physical examination, and radiographic evaluation including weight-bearing antero-posterior, lateral, and skyline views. Results There were 261 monks from 85 temples included in this study. The overall prevalence of radiographic knee osteoarthritis was 59.4%, with 29.6% having symptomatic radiographic knee osteoarthritis. The patterns of involvement were isolated tibiofemoral compartment (7.7%), isolated patellofemoral compartment (18.8%), and combined (32.9%). Obesity (OR 5.6, 95% CI; 1.6–19.8), age equal to or more than 60 years (OR 3.0, 95% CI; 1.5–6.0), and age at ordainment equal to or more than 46 years (OR 2.2, 95% CI; 1.1–4.6) were associated with risk of developing radiographic knee osteoarthritis. Obesity (OR 17.9, 95% CI; 2.4–132.1) and current smoking (OR 7.7, 95% CI; 2.4–24.3) were associated with symptomatic radiographic knee osteoarthritis. Severity of involvement was associated with obesity (OR 12.0, 95% CI; 2.3–60.9), older age (OR 3.8, 95% CI; 1.3–5.1), and older age at ordainment (OR 2.8, 95% CI; 1.3–6.1). Conclusions The prevalence of radiographic knee osteoarthritis with patellofemoral involvement in Thai monks is high and is more common among the elderly, those who were older at ordainment, and obese subgroups. Each pattern of knee osteoarthritis might have a different pathomechanism in the development of osteoarthritis.     

Femoral sulcus angle and increased patella facet cartilage volume in an osteoarthritic population

OBJECTIVE: The patellofemoral joint is an example of an incongruent articulation commonly affected by osteoarthritis (OA). The relationship between femoral sulcus angle and the development and progression of patellofemoral OA is unclear. The aim of this study was to examine the relationship between the femoral sulcus angle at baseline and patella cartilage volume at baseline and at 2-year follow-up among community based adults with established knee OA. METHODS: One hundred subjects had magnetic resonance imaging of their symptomatic knee at baseline and at 2-year follow-up. From these images, patella cartilage volume was determined. Radiographic skyline views of the patellofemoral joint were taken at baseline to measure the femoral sulcus angle. RESULTS: For every 1 degrees increase in the femoral sulcus angle (i.e., as the sulcus angle became more shallow) there was an associated 9.1mm3 (95% CI 3.1, 15.0) increase in medial patella cartilage volume at baseline (P=0.003). There was a similar trend that approached statistical significance between the femoral sulcus angle and the lateral patella facet cartilage volume at baseline (P=0.09). There was no association between the femoral sulcus angle at baseline and the change in patella cartilage volume over 2 years in either patellofemoral compartment. CONCLUSION: These results infer that the femoral sulcus angle is a cross-sectional determinant of the amount of patella cartilage, but is not a major determinant of the annual change of patella cartilage volume among people with knee OA. These data suggest that a shallower sulcus in the context of established OA may be an advantageous anatomical variant. Further longitudinal studies are required to determine the role of the femoral sulcus angle in OA.     

Biomechanical comparison of a new stand-alone anterior lumbar interbody fusion cage with established fixation techniques – a three-dimensional finite element analysis

Background

The aim of this study was to examine the prevalence of self-reported and clinical knee morbidity among floor layers compared to a group of graphic designers, with special attention to meniscal status.

Methods

We obtained information about knee complaints by questionnaire and conducted a bilateral clinical and radiographic knee examination in 134 male floor layers and 120 male graphic designers. After the exclusion of subjects with reports of earlier knee injuries the odds ratio (OR) with 95% confidence intervals (CI) of knee complaints and clinical findings were computed among floor layers compared to graphic designers, using logistic regression. Estimates were adjusted for effects of body mass index, age and knee straining sports. Using radiographic evaluations, we conducted side-specific sensitivity analyses regarding clinical signs of meniscal lesions after the exclusion of participants with tibiofemoral (TF) osteoarthritis (OA).

Results

Reports of knee pain (OR = 2.7, 95% CI = 1.5–4.6), pain during stair walking (OR = 2.2, 95% CI = 1.3–3.9) and symptoms of catching of the knee joint (OR = 2.9, 95% CI = 1.4–5.7) were more prevalent among floor layers compared to graphic designers. Additionally, significant more floor layers than graphic designers had clinical signs suggesting possible meniscal lesions: a positive McMurray test (OR = 2.4, 95% CI = 1.1–5.0) and TF joint line tenderness (OR = 5.4, 95% CI = 2.4–12.0). Excluding floor layers (n = 22) and graphic designers (n = 15) with radiographic TF OA did not alter this trend between the two study groups: a positive McMurray test (OR = 2.2, 95% CI = 1.0–4.9), TF joint line tenderness (OR = 5.0, 95% CI = 2.0–12.5).

Conclusion

Results indicate that floor layers have a high prevalence of both self-reported and clinical knee morbidity. Clinical knee findings suggesting possible meniscal lesions were significant more prevalent among floor layers compared to a group of low-level exposed graphic designers and an association with occupational kneeling could be possible. However, causality cannot be confirmed due to the cross-sectional study design.     

Static knee alignment and its association with radiographic knee osteoarthritis

OBJECTIVES: Although knee alignment is associated with the progression of knee osteoarthritis (OA), it is unclear which features that characterize radiographic OA are related to alignment. The aim of this study was to examine the relationship between static knee joint alignment (measured as a continuous variable) and the radiographic features of knee OA (joint space narrowing and osteophytes). METHODS: One hundred and twenty one adults with symptomatic knee OA were recruited using a combined strategy including referral from specialist centres, arthritis support groups and media advertising. X-rays were performed to classify the severity of disease and to determine static knee alignment. RESULTS: Increasing varus knee alignment was associated with increasing risk of medial compartment joint space narrowing (P < 0.001) and osteophytes (P = 0.005). Increasing valgus knee alignment was associated with an increased risk for lateral compartment joint space narrowing (P < 0.001) and osteophytes (P = 0.002). CONCLUSION: This study has demonstrated that the static knee angle, measured as a continuous variable, is an important determinant of the compartment-specific features of radiographic knee OA. Further work is required to determine whether interventions aimed at correcting these relatively minor levels of varus and valgus angulation will have an effect on the risk of tibiofemoral OA.     

Association between KLOTHO gene and hand osteoarthritis in a female Caucasian population

OBJECTIVE: Osteoarthritis (OA) is a common complex disease with strong heritable components. In this study, we investigated the association between four putatively functional genetic variants in KLOTHO gene, a strong ageing-related gene, and hand OA in a large female Caucasian population. METHODS: Subjects (n=1015, age range 33-74 years) were selected from the TwinsUK Registry. Radiographs of both hands were taken for each individual with standard posteroanterior view. The presence/absence of radiographic OA, osteophyte and joint space narrowing (JSN) was assessed using a standard atlas. Four putatively functional single nucleotide polymorphisms (SNPs) in KLOTHO gene were genotyped using allelic discrimination assay. Association was initially estimated using Pearson's chi(2) or Fisher's exact test at allelic and genotypic levels. The direction and magnitude of significant association were further investigated by robust logistic regression with age as a covariate. RESULTS: We found significant association between SNP G-395A and the presence/absence of radiographic hand OA and osteophyte, but not JSN. Allele G significantly increased the risk for radiographic hand OA and osteophytes with odds ratios (ORs) of 1.44 (P=0.008, 95% confidence interval (CI) 1.09-1.91) and 1.36 (P=0.006, 95% CI 1.09-1.70), respectively. From logistic regression modelling, genotype GG showed more than three-fold increased risk for both radiographic hand OA (OR=3.10, 95% CI 1.10-8.76) and osteophyte (OR=3.10, 95% CI 1.10-8.75) when compared to genotype AA. After adjustment for age, ORs for genotype GG further increased to 4.39 (P=0.006, 95% CI 1.51-12.74) for radiographic hand OA and to 4.47 (P=0.005, 95% CI 1.56-12.77) for osteophytes. CONCLUSIONS: Our results suggest that one variant in KLOTHO gene is associated with the susceptibility of hand OA and appears to act through osteophyte formation rather than cartilage damage.     

Association between radiological findings and symptoms at the patellofemoral joint in advanced knee osteoarthritis

We investigated the association between the radiological findings and the symptoms arising from the patellofemoral joint in advanced osteoarthritis (OA) of the knee. Four radiological features, joint space narrowing, osteophyte formation, translation of the patella and focal attrition were assessed in 151 consecutive osteoarthritic knees in 107 patients undergoing total knee replacement. The symptoms which were assessed included anterior knee pain which was scored, the ability to rise from a chair and climb stairs, and quadriceps weakness. Among the radiological features, only patellar translation and obliteration of the joint space had a statistically significant association with anterior knee pain (odds ratio (OR) 4.85; 95% confidence interval (CI) 1.83 to 12.88 and OR 11.23; 95% CI 2.44 to 51.62) respectively. Patellar translation had a statistically significant association with difficulty in rising from a chair (OR 9.06; 95% CI 1.75 to 45.11). Other radiological features, including osteophytes, joint space narrowing, and focal attrition had no significant association. Our study indicates that the radiological findings of patellar translation and significant loss of cartilage are predictive of patellofemoral symptoms and functional limitation in advanced OA of the knee.